Cardiac assistance device

ABSTRACT

A cardiac assistance device is disclosed which produces a unidirectional pumping action assisting the heart when the device is activated after it has been introduced into a blood vessel by conventional surgical procedures.

United States Patent Goetz et al.

[541 CARDIAC ASSISTANCE DEVICE [72] Inventors: Robert H. Goetz; LionelJ. Goetz, both of 80 Vernon Drive, Scarsdale, NY. 10583 22 Filed:Feb.ll,1970

21 App1.No.: 10,452

I Coronary Artery Aortic I Volve I ll 1 I l ';-i 7 l 74 :1 1 I [1513,692,018 51 Sept. 19, 1972 3,505,987 4/l970 Heilman 128/1 R FOREIGNPATENTS OR APPLICATIONS 15,864 7/1912 France ..l28/344 OTHERPUBLICATIONS Laird et al. Trans. Amer. Soc. Artif. Int. Organs. Vol.XIV, 1968 pp. 338- 342 Primary Examiner-Dalton L. TruluckAttorney-Pennie, Edmonds, Morton, Taylor and Adams [5 7 ABSTRACT Acardiac assistance device is disclosed which produces a uni-directionalpumping action assisting the heart when the device is activated after ithas been introduced into a blood vessel by conventional surgicalprocedures.

8 Claims, 5 Drawing Figures PATENTED SEP 19 I 3 6 92.018

sum 2 OF 2 Cororid Arrery Femovol Artery INVENTORS ROBERT H. GOETZ BYLIONEL JVGOETZ ATTORNEYS BACKGROUND OF THE INVENTION Heart failure ismedically defined, in its broadest sense, as the inability of the heartto pump blood throughout the body. For purposes of describing thepresent invention a failing heart is defined as one that is notsufficiently healthy to pump blood at the rate needed to maintainadequate blood flow and continued well-being of its owner but which isnevertheless, capable of pumping some blood.

A cardiac assistance device is one that aids a failing heart. Onepresently known device .used for this purpose comprises a singleinflatable balloon which is adapted to be inserted into an appropriateblood vessel, as for example, the aorta. When such a device is inflatedand deflated, a pumpingaction within theblood vessel occurs and when theinflation and deflation cycle is appropriately timed to the heartbeat,the device acts to assist the failing heart.

While this type of cardiac assistance device has significantlycontributed to the progress of medical science, it is inherentlyinefficient. This is due to the fact that the balloon acts as anomni-directional pump thus making it impossible to direct its force in asingle direction so that blood is pumped only to those regions of h thebody where adequate blood flow is most critical as for example, to thebrain and the muscles of the heart itself.

SUMMARY OF THE INVENTION In accordance with the teachings of the presentinvention a cardiac assistance device is provided which is constructedto create an artificially induced unidirectional pumping action, withina blood vessel of the patient to aid the failing heart. In construction,the device includes an inflatable occluding chamber and one or moreinflatable pumping chambers disposed on one side of the occludingchamber in communicating relationship therewith. The occluding andpumping chambers are adapted to be inserted into the blood vessel of thepatient and both are inflated and deflated on a cyclical basis out ofphase with the beat of the failing heart but sequentially with respectto each other by a pneumatic power source positioned externally of thepatient.

The occluding chamber has a diameter greater than the diameter of theblood vessel within which it lies so that when inflated it occludes theblood vessel. Since the occluding chamber is inflated before the pumpingchamber, the pressure created in the blood vessel when the pumpingchamber is later inflated causes the blood to flow in a single directionaway from point of occlusion between the inflated occluding chamber andthe wall of the blood vessel. Thus the cardiac assistance device of thepresent invention acts as a uni-directional pump and when properlypositioned the direction of blood flow created by the device can beeffectively controlled according to the dictates of sound medicalpractice to be most beneficial to the patient.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view ofthe cardiac assistance device of this invention disposed within a bloodvessel.

FIG. 2 is a cross-sectional view of the cardiac assistance device ofthis invention disposed within a blood vessel showing an alternativeembodiment of the structure within the occluding chamber.

FIGS. 3 and 4 are elevation views of the cardiac assistance device ofthis invention showing progressive stages of the operation of thedevice.

FIG. 5 is a diagrammatic illustration of a human heart showing theplacement of thecardiac assistance device within the aorta.

DETAILED DESCRIPTION OF THE INVENTION As shown in FIG. 1, the cardiacassistance device includes a pumping structure indicated generally byreference numeral 10 which is adapted to be inserted within a bloodvessel 2 of the patient by conventional surgical procedures. The pumpingstructure is specially constructed to produce auni-directional flow ofblood within the blood vessel. For this purpose the pumping structureoperates to first occlude the blood vessel and then to create pressurewithin the blood vessel on one side of the point of occlusion to therebycause the blood within the vessel to flow in one direction away from thepoint of occlusion. In construction, the pumping structure includesexpansion means for internally occluding the blood vessel and bloodmoving means positioned on one side of the expansion means fordisplacing blood onthat side of the expansion means. As shown, theexpansion means comprises an inflatable occluding chamber 3 and theblood moving means comprises one or more inflatable pumping chambers 4which communicate in series with the occluding chamber. The occludingchamber 3 and the pumping chamber 4 are defined by a balloon structurewhich consists of a balloon member 5 mounted on a tubular conduit 6extending longitudinally through the balloon member 5. Each end of theballoon is disposed in fluidgas tight relationship about the tubularconduit by suitable sealing means as for example, silk threads 7 tiedtightly about the terminal ends of the balloon member. As shown, anintermediate portion of the balloon member 5 is held against expansionin fluid-gas tight relationship to the tubular conduit 6 by silk threads7' similar to the ones used for sealing each end of the balloon member.A metallic pellet 13 seals the end of the tubular conduit at a pointlocated near the end of the pumping chamber 4 remote from the occludingchamber. The use of a metallic pellet for this pur pose advantageouslypermits the position of the pumping structure within the blood vessel tobe visually monitored by the use of standard X-ray techniques after ithas been introduced into the patient.

The balloon member 5 and the tubular conduit are made of nonthrombogenicmaterial so that the danger of blood clotting is eliminated. Also thesilk sealing threads are coated with a nonthrombogenic material and theassembled pumping structure is dipped into a bath of moltennonthrombogenic material. An example of nonthrombogenic material ispolyurethane. In addition to being nonthrombogenic, the balloon memberis also inelastic or nonstretchable so that the danger of fatiguefailure due to stretching when the balloon member is repeatedly inflatedand deflated is avoided. In other words, no stretching of the balloonmember occurs when it is inflated. Rather the balloon merely expandsupon inflation to its natural but relaxed inflated state.

The tubular conduit serves a dual purpose. First, it acts to hold thepumping chamber on one side of the occluding chamber as the balloonstructure is introduced into the patient thus preventing the balloonstructure from folding back on itself. Secondly, the tubular conduitprovides a convenient means for introducing gas or fluid into theballoon structure to inflate the occluding and pumping chambers. For thelatter purpose those portions of the tubular conduit which extendthrough the occluding and pumping chambers are provided with a series ofperforations 8 which permit air flow into and out of the occluding andpumping chambers. In the presently preferred embodiment of thisinvention, the tubular conduit has a diameter of approximately 2-3millimeters and the perforations are approximately 1 millimeter indiameter.

The occluding chamber of the balloon has a size such as when inflatedthe blood vessel is internally occluded. The blood vessel is occluded bythe inflated occluding chamber in the sense that a complete occlusion ofthe blood vessel is produced causing stoppage of the blood stream andaccumulation of the pressure within the blood vessel. The pumpingchamber on the other hand is slightly smaller in size than the occludingchamber and when inflated the pumping chamber acts only to increase thepressure within the blood vessel. In other words, flow of blood past theinflated pumping chamber is not prevented but blood flow past theinflated occluding chamber is prevented. In the construction shown inthe drawing, the occluding chamber is substantially spherical in shapewhile the single pumping chamber shown is substantially cylindrical inshape. Since the construction shown in the drawing is intended forinsertion within the aorta of the patient which for the average patienthas an inside diameter of approximately 18-22 millimeters, it ispreferred that the spherical occluding chamber be slightly greater than22 millimeters in diameter in its inflated state and that the pumpingchamber have an inflated size of approximately 16 millimeters indiameter.

The occluding and pumping chamber of the balloon are alternatelyinflated and deflated at a cycle which is out of phase with theheartbeat of the patient. That is, when the heart is relaxed, thechambers of the balloon are inflated and when the heart is pumping thesechambers are deflated. For this purpose a pneumatic power sourceindicated diagrammatically by reference numeral 11 in FIG. is provided.The pneumatic power source is of conventional construction having thecapability of creating alternating positive and negative pressure astriggered by the electrocardiogram of the patient. As shown, the pumpingmachine is connected to the balloon structure via the tubular conduit 6.A suitable pumping machine for practicing the teachings of the presentinvention is the pneumatic pumping machine produced by the DatascopeCompany of New Jersey.

In order to provide uni-directional pumping action, the occludingchamber of the balloon structure is inflated prior to inflation of thepumping chamber. For this purpose an obstruction member 9 is provided.The obstruction member acts to divert the flow of gas within the balloonstructure in a manner which produces sequential inflation of theoccluding and pumping chambers. As shown the obstruction member isdisposed within that portion of the tubular conduit extending throughthe occluding chamber 3 at a point located between two adjacentperforations 8' and 8". With this arrangement, gas supplied from thepneumatic power source is temporarily diverted from the tubular conduitinto the occluding chamber through the perforations 8" disposed upstreamof the obstruction member. This diversion is due to the presence of theobstruction member which prevents uninterrupted flow of gas through thetubular conduit. When the occluding chamber has reached a fully inflatedconfiguration as shown in FIG. 4, the gas reenters the tubular conduitthrough the perforations 8' disposed downstream of the obstructionmember. From this point the gas flows into the pumping chamber throughthe perforations disposed in the portion of the tubular conduitextending within the pumping chamber. Thereby the pumping chamber isbrought to a fully inflated condition as shown in FIG. 1. Thus it willbe seen that the occluding chamber and pumping chambers are repeatedlycycled in a sequential fashion from the configuration shown in FIG. 3where both chambers are collapsed to the configuration shown in FIG. 4where the occluding chamber is inflated and the pumping chamber deflatedand finally to the configuration shown in FIG. 1 wherein both chambersare inflated causing blood within the vessel to flow in the direction ofarrows 14 away from the point of occlusion in the vessel created by theinflated occluding chamber. With the solid obstruction member it will berecognized that deflation of the occluding chamber also occurs in asequential manner. In other words, during the deflation phase a reverseflow of air out of the balloon is created first from the occludingchamber through the perforations 8' and then from the pumping chamber.The path of exit from the pumping chamber leads into the conduit 6through the perforations disposed in the portion of the conduit 6located within the pumping chamber and then into the occluding chambervia the perforations 8 and finally back into the tubular conduit throughthe perforations 8" and out of the balloon structure.

The occluding and pumping chambers may advantageously be deflatedsubstantially simultaneously by replacing the solid obstruction memberwith a oneway valve such as the ball valve 12 shown in FIG. 2. With thisarrangement, the ball valve is closed during the inflation cycle therebyproducing the same pattern of air flow as is produced with the solidobstruction member shown in FIG. 1. However, on the deflation cycle, theball valve is opened thus permitting air to be withdrawn from theoccluding and pumping chambers through all the perforations in thoseportions of the tubular conduit disposed within these chambers atsubstantially the same time. Simultaneous deflation of the occluding andpumping chambers is advantageous since very little time is consumedbetween successive beats of the heart. Thus the possibility that thepumping structure will pulsate in appropriate coordination with theheartbeat is thereby greatly enhanced.

One application for the cardiac assistance device of the presentinvention is sown in FIG. 5. For this application the pumping structuresection of the device is inserted into the femoral artery at a pointbelow the bifurcation in the aorta and pushed upward into the aorta tothe position shown. In this position the device acts to direct a flow ofblood toward the heart into the coronary artery which supplies blood tothe heart muscles and also into the carotid arteries which supply bloodto the brain. Blood pumped by the cardiac assistance device is preventedfrom reentering the heart chamber by the aortic valve. It will berecognized that this particular use of the device is particularlybeneficial since an adequate supply of blood to these critical organs isinsured.

We claim: 1. A cardiac assistance device comprising: a. a pump structureadapted to be inserted into a blood vessel of a patient, said bloodstructure having an elongated support means with an insertable end;

1. expansion means on said support means for occluding the blood vessel;

2. blood moving means positioned on one side of the expansion means onsaid support means adjacent said insertable end for displacing bloodwithin the vessel on said one side;

3. means for sequentially activating the expansion means and bloodmoving means in that order to produce a uni-directional flow of bloodwithin the blood vessel away from the point of occlusion and toward theheart, and

b. means for alternately activating and deactivating the expansion meansand to produce moving means on a cycle out of phase with the pumpingaction of the heart.

2. The cardiac assistance device according to claim 1 wherein:

a. the expansion means comprises an inflatable occluding chamber; and

b. the blood moving means comprises at least one inflatable pumpingchamber communicating with the occluding chamber.

3. The cardiac assistance device according to claim 2 wherein:

a. the occluding chamber and pumping chamber are troduced into thepatient.

4. The cardiac assistance device according to claim 3 wherein:

a. the holding means comprises a tubular conduit extending through theballoon member, said balloon member being held in sealed relationshipabout said conduit at each end thereof and at said intermediate pointalong its length; and

b. the means for activating the occluding and pumping chambers comprisesa pneumatic power source operatively connected to the: tubular conduitfor alternately pressurizing and depressurizing the balloon member toinflate and deflate it respectively;

c. 33: portion of the tubular conduit extending through the balloonmember has a series of perforations permitting flow of air into and outof the balloon member during the inflation and deflation I phasesrespectively.

5. The cardiac assistance device according to claim 4 wherein:

a. the means for sequentially inflating the occluding and pumpingchambers comprises means for temporarily diverting the flow of airthrough the tubu lar conduit into the occluding chamber prior toentrance into the pumping chamber.

6. The cardiac assistance device according to claim 5 wherein:

a. the means for diverting the flow of air through the tubular conduitcomprises an obstruction member disposed within the portion of thetubular conduit extending through the occluding chamber at a pointlocated between two adjacent perforations of said conduit portion.

7. The cardiac assistance device according to claim 5 wherein:

a. the means for diverting the flow of air through the

1. A cardiac assistance device comprising: a. a pump structure adaptedto be inserted into a blood vessel of a patient, said blood structurehaving an elongated support means with an insertable end;
 1. expansionmeans on said support means for occluding the blood vessel;
 2. bloodmoving means positioned on one side of the expansion means on saidsupport means adjacent said insertable end for displacing blood withinthe vessel on said one side;
 3. means for sequentially activating theexpansion means and blood moving means in that order to produce auni-directional flow of blood within the blood vessel away from thepoint of occlusion and toward the heart, and b. means for alternatelyactivating and deactivating the expansion means and to produce movingmeans on a cycle out of phase with the pumping action of the heart. 2.blood moving means positioned on one side of the expansion means on saidsupport means adjacent said insertable end for displacing blood withinthe vessel on said one side;
 2. The cardiac assistance device accordingto claim 1 wherein: a. the expansion means comprises an inflatableoccluding chamber; and b. the blood moving means comprises at least oneinflatable pumping chamber communicating with the occluding chamber. 2.holding means attached to the balloon member for maintaining therelative position of the occluding chamber and pumping as they areintroduced into the patient.
 3. The cardiac assistance device accordingto claim 2 wherein: a. the occluding chamber and Pumping chamber aredefined by a balloon structure comprising:
 3. means for sequentiallyactivating the expansion means and blood moving means in that order toproduce a uni-directional flow of blood within the blood vessel awayfrom the point of occlusion and toward the heart, and b. means foralternately activating and deactivating the expansion means and toproduce moving means on a cycle out of phase with the pumping action ofthe heart.
 4. The cardiac assistance device according to claim 3wherein: a. the holding means comprises a tubular conduit extendingthrough the balloon member, said balloon member being held in sealedrelationship about said conduit at each end thereof and at saidintermediate point along its length; and b. the means for activating theoccluding and pumping chambers comprises a pneumatic power sourceoperatively connected to the tubular conduit for alternatelypressurizing and depressurizing the balloon member to inflate anddeflate it respectively; and c. the portion of the tubular conduitextending through the balloon member has a series of perforationspermitting flow of air into and out of the balloon member during theinflation and deflation phases respectively.
 5. The cardiac assistancedevice according to claim 4 wherein: a. the means for sequentiallyinflating the occluding and pumping chambers comprises means fortemporarily diverting the flow of air through the tubular conduit intothe occluding chamber prior to entrance into the pumping chamber.
 6. Thecardiac assistance device according to claim 5 wherein: a. the means fordiverting the flow of air through the tubular conduit comprises anobstruction member disposed within the portion of the tubular conduitextending through the occluding chamber at a point located between twoadjacent perforations of said conduit portion.
 7. The cardiac assistancedevice according to claim 5 wherein: a. the means for diverting the flowof air through the tubular conduit comprises a one-way valve disposedwithin the portion of the tubular conduit extending through theoccluding chamber at a point located between two adjacent perforationsof said conduit portion, said valve precluding the flow of airtherethrough during the inflation phase and permitting flow of airtherethrough during the deflation phase.
 8. The cardiac assistancedevice according to claim 5 wherein: a. the occluding chamber issubstantially spherical in shape; and b. the pumping chamber issubstantially cylindrical in shape.